Sanitary liquid filling pumps are used for various applications. In particular, such pumps are used in the food packaging industry to transfer liquid food products such as juice, milk and the like from bulk storage to individual product package units.
Various types of pumps are known in the art. One known type of pump system includes a bulk food product storage tank, a pump and a filling nozzle for filling the individual product packages. In one commercially available system, the pump is oriented vertically and receives the liquid food product at the bottom thereof. The food product is pumped upwardly through the pump into the filling nozzle. At the filling nozzle, the liquid is redirected downwardly into the individual packages.
It has been observed that direction changes in the liquid food product flow path tend to create turbulence in the flowing liquid which can result in foaming. However, it is desirable to avoid foaming for a number of reasons. First, the foamed volume of the food product is greater than an equivalent liquid volume. Thus, the product package could be short filled, or, conversely, the foam could overflow from the package. Second, foaming can result in backflow through the pump and associated system components. Given the high standards of cleanliness established for the food processing industry, such backflow is to be avoided to prevent possible contamination of the pump and associated equipment. Foaming can also adversely impact the overall filling and packaging process and process controls.
In an effort to overcome the foaming problem as well as other, maintenance related problems associated therewith, one known apparatus includes a horizontally oriented pump which discharges into a vertically oriented filling nozzle. Notwithstanding that the directional changes in the product flow path are reduced in such an arrangement, there remains at least one large or extreme directional change in the flow path. Moreover, such angled mounting configurations have added to the complexity of the filling apparatus and thus the overall maintenance required to maintain the system operational.
Accordingly, there continues to be a need for a filling pump which reduces or eliminates turbulence in the flowing food product and the foaming associated therewith. Such a filling pump should provide a straight-through pumping profile with minimum flow obstructions for the flowing food product.